Get your own Free Homepage
On computed tomography, a simple renal cyst is seen at the well-defined lesion with central low attenuation values consistent with fluid. A renal cell carcinoma, however, is poorly defined and demonstrates decreased attenuation which is heterogeneous and not equivalent to fluid. This decreased attenuation is consistent with elements of necrosis. Calcification can be seen in these lesions as well. CT is helpful in staging and evaluating renal cell carcinoma for capsular extension, lymph node enlargement and renal vein involvement.
The case of Mr. Kollick demonstrates a fairly well circumscribed solid lesion within the upper pole of the right kidney with central areas of necrosis. No lymphadenopathy or evidence for invasion into the renal vein can be demonstrated. The accompanying ultrasound clearly demonstrates the mass as a circular area of increased echogenicity with central heterogeneous decreased echogenicity. These areas of decreased echos are again consistent with elements of necrosis. (The lesion is outlined by black arrowheads on the CT scan and arrows on the US.)
(Prepared by Michael P. Buetow, M.D.)
Back to Case 15: Macroadenoma (Prolactinoma)
Return to Radiology for Medical Students
Get your own Free Homepage